1. Field of the Invention
The present invention relates to a package structure for connection with an output/input module, and particularly to a package structure that allows easy replacement of an output/input module connected therewith.
2. Description of Prior Art
In the current electronic industry, electronic components such as multi-chip packages and system in packages (SIPs) are generally fixed on a substrate and electrically connected to metal traces on the substrate by a lead frame and a plurality of solder bumps. Under the demands for light, thin, short, small and high performance electronic products, the electronic components in these electronic products and the contact pins thereof are both increased in number and reduced in size.
The solder bumps play an important role since they are responsible for the transmission of electrical signals. Once the solder bumps are damaged, the electronic components may be damaged and thus the entire electronic component may fail in function. Damage of the solder bumps is generally due to thermal fatigue when they are subjected to high temperature variations. It is well known that a package structure consists of several parts among which the solder bumps are the ones that are located at the connection interfaces of the package structure. When subjected to high temperature variations, the solder bumps induce a significant amount of thermal stress therein. This thermal stress causes the solder bumps to crack and peel, leading to failure of the package structure. The lower the height of the solder bumps, the greater the thermal fatigue damage to the solder bumps. Accordingly, for a light, thin, short, small and high performance package structure, the life span of such a package structure is directly impacted by the solder bumps.
In case that such problems occur, it is necessary to repair or replace the electronic components that are damaged due to the damage of the solder bumps, so that the normal operation of the electronic product containing these components can be maintained. Since these electronic components are generally reflow soldered by conventional reheating techniques to securely and electrically affix the components to a circuit board, rework of the solder joints must be performed when repairing or replacement of the electronic components is required. However, in some situations, such as for a flip-chip package or a three-dimensional package, reworkability is generally not available. For a flip-chip package, the underfills thereof that are mainly epoxy-based materials are not reworkable after curing. Three-dimensional (3D) packages, which are one kind of SiP (System in Package) packages, are characterized in reduced package volume and initial system integration. However, most of current 3D package architectures are not reworkable.
In the development stage of electronic products, various experiments and testing procedures must be conducted. Currently, electronic components of the electronic products are first mounted on a substrate by the conventional soldering technology, and then testing is carried out to check whether the function of the electronic product is satisfactory. If the tested electronic product is unsatisfactory in performance or fails in function, electronic components of the tested product that are found to be not properly functioning must be replaced. However, after the replacement and rework of these electronic components, the reliability of the electronic product may be impaired and even the function of the electronic product may be adversely affected.
Hence, an improved package structure is desired to address the repair, replacement and updating problems of electronic components thereof that are encountered in the prior art.